The invention relates to a reel-up for reeling of a fiber web. Especially the invention relates to a reel-up for reeling of a fiber web around a reel spool to form a parent roll by use of a reeling nip between a reeling cylinder of the reel-up and the parent roll under reeling, which reel-up has a primary reeling position and a secondary reeling position, which reel-up comprises the reeling cylinder, substantially horizontal guides and for each end of the reel spool loading arms and carriages.
As known from the prior art, fiber web producing processes typically comprise an assembly formed by a number of apparatuses arranged consecutively in the process line. A typical production and treatment line comprises a head box, a wire section and a press section as well as a subsequent drying section and a reel-up. The production and treatment line can further comprise other sections and devices for finishing the fiber web, for example a sizer, a coating device, and a calender. The production and treatment line also comprises at least one slitter-winder for forming customer rolls as well as a roll packaging apparatus. And, as known, fiber webs, such as paper or board webs, are manufactured in machines together forming a fiber web manufacturing line, which may be hundreds of meters long.
In fiber web manufacturing lines, manufacturing operates as a continuous process. The finished fiber web being output from the machine is wound with a reel-up around a reeling shaft, i.e. a reel spool, into a parent roll (a machine roll), the diameter of which may be more than 5 meters and which may weigh more than 160 tons. The purpose of the reeling is to transfer the fiber web from its planar manufacturing form into a form in which it can be handled more easily.
At the reel-up the continuous process of the machine is interrupted for the first time, after which the process continues in stages. Every attempt is made to interlink these stages as smoothly as possible. The reel-up typically comprises a reeling cylinder and two pairs of carriages or two pairs of forks or a pair of carriages and a pair of forks, one carriage/fork for each end of the reel spool/parent roll for moving and supporting the reel spool and the parent roll to be reeled. The web is reeled around the reel spool to a parent roll by means of a reeling nip between the reeling cylinder and the parent roll under reeling, which reeling takes place in a primary stage in a primary position and in a secondary stage in a secondary position. In most prior art arrangements the reel spool rotates during reeling on the guides supported by its rotating bearing housing.
The reel-up is thus a device that reels a material, which is produced as a continuous fiber web in a fiber web production line, into the form of a roll; the parent roll. In the production process of the fiber web, the reeling is generally a first process part, wherein a continuous process is discontinued to be continued in sequences. The parent roll is formed around the reeling shaft that functions as a core of reeling, i.e. the fiber web on one parent roll has a beginning and an end. At a reel-up a certain amount of fiber web is wound around the reel spool, typically without slowing down the running speed of the fiber web, after which the so-called turn-up is performed, in which the web is cut and directed to be reeled around a new empty reel spool. The smooth operation of the reel-up and especially the turn-up is very critical with regard to the function of the entire production line and, it is therefore important that handling of the reel spools, the parent rolls under reeling and the finished parent rolls is reliable and such that the turn-up can be performed as required.
A prior art method described in the FI-patent 91383 (EP 0483092 B1) changed the size of parent rolls into a new order, since it was possible to build the first part of the parent roll without affecting the properties of the fiber web that was to be reeled. One feature that improved the technology was the progressive center torque of the parent roll that was provided by means of primary and secondary drives, enabling the versatile use of reeling parameters in building the parent roll. The prior art also discloses an example in which primary and secondary drives are engaged by a drive unit, with which the reeling shaft of the parent roll to be reeled is engaged during reeling with the help of a cylinder arrangement located in connection with transmission. This arrangement has been described in U.S. Pat. No. 5,069,394 and the drive arrangement is engageable and detachable by means of a cylinder device. In this kind of reel-up the primary center drive and the primary carriage as well as the secondary center drive and the secondary reeling carriage move simultaneously, since the center drive is mechanically constructed in connection with the carriage and they are moved by the same actuator.
A prior art method described in U.S. Pat. No. 5,370,327 introduced the idea that a parent roll would be built so that the parent roll would be on horizontal guides and at the same vertical height throughout the reeling. The present invention relates to this type of reel-up. FI-patent 91383 also presented this type of solution, but, before beginning to reel, the reeling shaft was moved along a curved path into its initial reeling position. In the reel-up according to the U.S. Pat. No. 5,370,327 a moving reeling cylinder makes it possible to keep the center of the reeling shaft on a constant level. One advantage of this solution is changing the adjustment of the nip power from loading on the side of the parent roll to loading on the side of a constant mass reeling cylinder.
In US patent publication 5,673,870 is disclosed a reel apparatus for reeling a traveling web produced on a papermaking machine, which comprises a rotatable support drum, which is fixedly mounted in a frame and a pair of parallel, horizontally disposed guides mounted to the frame with the tops of the guides above the apex of the support drum. New reel spools are brought into supporting engagement on the guides at a location downstream of the apex of the support drum and intermediate the apex of the support drum and a jumbo-sized wound web roll which is being wound while being powered by a center wind assist drive, as well as nipping engagement with the support drum. Each reel spool is supported in a pair of carriages which are mounted to travel over the guides. In the reel apparatus two sets of a complimentary pair of carriages can be disposed about a single pair of guides to handle two different reel spools simultaneously as one reel spool begins the web reeling process and the other reel spool is finished being wound.
In WO publication 2010000915 is disclosed a reel-up for continuous reeling of fiber web around a reeling shaft to form a parent roll, the reel-up comprising a reeling cylinder, whereby a nip load can be formed between the parent roll and the reeling drum cylinder, the parent roll being arranged so as to be movable during the reeling along a substantially horizontal path from the starting point of the reeling to the point of transfer of the completed parent roll, the starting point of the reeling being upstream of the reeling cylinder and the point of transfer downstream of the same. Upstream of the reeling cylinder, there are primary support means for supporting the parent roll against the reeling cylinder and downstream of the reeling drum, there are secondary forks for supporting the machine roll against the reeling drum.
In some types of known prior art reel-ups one possibility of moving the reeling shaft and the parent roll is to construct two carriage pairs, one carriage for each end of the reeling shaft/the parent roll for the movement. It is also known from prior art to construct for movements of the reeling shaft and the parent roll a combination of a carriage pair and a fork pair. In order to transfer the parent roll from one carriage to the other the paths of the carriages must be able to meet. One possibility known from prior art would be to construct one carriage pair outside the guides of the reel-up and another carriage pair inside the guides of the reel-up but in reel-ups with center drives the drives must be located outside the guides, which creates the problem of synchronizing the position between the center drive and the carriage pair moving inside the guides of the reel-up as the synchronizing is done electrically and it must be very accurate and stable, since otherwise the nip load of reeling is disturbed. The synchronizing can also be done mechanically by using two carriages for each carriage of a carriage pair; one carriage above and one carriage below the end of the reel spool but this construction is complicated and large and thus expensive. Synchronizing is necessary especially in change of the drive when the secondary drive is engaged to the parent roll in reeling speed. Two sets of carriages also increase the costs.
In the reel-ups according to prior art, for example according to those mentioned above, in the primary reeling position the reel spool around which the fiber web is reeled to form a parent roll is moved during reeling. This requires space and sets challenges for construction of the reel-up. This also lengthens the production line.